• Journal of Korean Society of Forest Science
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• v.108 no.2
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• pp.147-167
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• 2019

This study was conducted to analyze forest vegetation structure in the Marugeum (Ridge) area of Gitdaebaegibong to Jukryeong, Baekdudaegan. Data were collected in 298 quadrates through a Braun-Blanquet vegetation survey from April, 2018 to October, 2018. Forest vegetation was classified into 13 vegetation units. A Quercus mongolica community was divided into Morus bombycis, Filipendula glaberrima, Fraxinus sieboldiana, Prunus maackii unit and Q. mongolica typical unit. The M. bombycis unit was further classified into a Deutzia glabrata group and M. bombycis typical group. The F. glaberrima unit was subdivided into a Veratrum oxysepalum group, Arundinella hirta group, and F. glaberrima typical group. The F. sieboldiana unit was divided into a Pinus densiflora group, Larix kaempferi group, and F. sieboliana typical group. The relationship between vegetation units and environmental factors was studied through coincidence analysis and CCA. The F. glaberrima unit (VU 6~8) was distributed by elevation above 1,200 m and other vegetation units were distributed below 1,200 m. Results of the CCA analysis showed that the F. glaberrima unit distribution is positively correlated with elevation. As a result of species diversity, the F. glaberrima unit was higher than other vegetation units. A similarity index analysis revealed that the F. sieboldiana unit (VU 9~11) was relatively homogeneous, and the M. bombycis unit (VU 1~5) and A. girta group (VU 7) were relatively heterogeneous. A detrended correspondence analysis determined that the distance between the statistical axes of the M. bombycis and F. glaberrima units was the greatest, which is consistent with the analysis of the similarity index. As a result of interspecific correlation of major woody plants, hydrophilic species were positively correlated, and a negative correlation was found between Q. mongolica and intolerant species such as P. densiflora and L. kaempferi.

• Korean Journal of Ecology and Environment
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• v.52 no.2
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• pp.105-117
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• 2019

In order to investigate the characteristics of benthic macroinvertebrate communities in the Gihwa stream, a tributary of the Dong River, we surveyed the community and environmental factors in April and November 2013 at 6 sites. The benthic macroinvertebrate taxa represented total 63 species belonging to 29 families, 12 orders, 5 classes and 4 phyla. Total 48 (10~28 in each site) species were collected in April and 44 (13~24 in each site) in November. The number of individuals increased slightly from $560{\sim}2,290m^{-2}$ in April to $806{\sim}3,674m^{-2}$ in November. Chironomidae spp. was dominant species in April and Stenopsyche bergeri was dominant species in November. In the Functional Feeding Groups, Gathering-collector(53.9%) was dominant in April, while Filtering-collector (44.3%) increased in November. Intolerant order category (i.e. EPT species richness) in St.1, St.5 and St.6 increased in November compared to April due to the increase of Trichoptera. St.2, St.3 and St.4, which were located near the fish farm, were low EPT as a whole, but Benthic macroinvertebrate index (BMI) was good state in November than April due to decrease of Chironomidae spp.. The environmental factors in the survey site showed similar tendency except for St.1 between both seasons, and electrical conductivity, salinity, and water width showed seasonal differences. Cluster analysis and Nonmetric multidimensional scaling (NMDS) based on benthic macroinvertebrate community data were divided into two groups according to season. Electrical conductivity, salinity and substrate composition were the most influential factors determining the distribution patterns of macroinvertebrate communities.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.20-24
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• 2019

Purpose Molecular Breast Imaging (MBI) scan is used in nuclear medicine, for which $^{99m}Tc-sestaMIBI$ is administered by intravenous injection. However, the breast uptake rate of $^{99m}Tc-sestaMIBI$ is less than 1% of the total dose administered, relying on blood flow conditions of organs. The purpose of this study is to evaluate the impact of changes to body temperature on the uptake of $^{99m}Tc-sestaMIBI$ in breast tissue. Materials and Methods We investigated 30 breast cancer patients who performed more than one follow-up MBI scan. All scans were acquired by Discovery 750B (Genral Electric Healthcare, USA). $^{99m}Tc-sestaMIBI$ injected with 740 MBq (20 mCi), after 60 minutes, gained bilateral breast CC (CranioCaudal), MLO (Medio Lateral Oblique) View. The follow-up examination was then classified into 15 body temperature control group and 15 body temperature non-control group, and gained breast image in the same way as before. The breast uptake rate was analyzed in the MLO View of the opposite side of the lesion, and blind images were evaluated. Results The breast uptake rate increased by 30.31% in the body temperature control group and it was statistically significant(P<0.05), and 0.96% in the body temperature non-control group, and it was not statistically significant(P=0.955). There was a significant difference in the uptake rate between the body temperature control and the non-control group of P value of 0.01. Evaluation of blind images showed significant results in terms of the quality of the images. Conclusion Increased breast tissue uptake was observed when the subject was kept warm. When the body temperature was raised after injection, dilation of the peripheral blood vessels can be achieved. As a result, the blood flow became smooth and the breast uptake rate increased. In addition, an increase in breast tissue uptake will improve the quality of images.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.245-265
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• 2019

Biotope, which represents the characteristic habitats of living organisms, need to be identified as essential for the efficient creation and sustainable management of urban ecosystems. This study was carried out to provide the basic information for ecological urban planning by analyzing types and attributes of the biotop established throughout the whole area of the Pohang city, a representative industrial city in Korea. The biotop established in Pohang city is composed of 12 types including forests (coniferous, deciduous, and mixed forests), agricultural fields (rice paddy and upland field), green facilities, river, reservoir, bare ground, residential area, public facilities, commercial area, industrial area, roads, and schools. As a result of analyzing the properties according to biotop types, industrial, commercial and residential areas, which represent urban areas, was dominated by introduced vegetation. Moreover the introduced vegetation is usually composed of exotic plants or modified forms for landscape architecture and horticulture rather than native plants, which reflects ecological property of both region and site. As the distance from the urban center increases, the agricultural field showed a form of typical farmland, whereas the closer it is, the more form of greenhouse farming. Natural green spaces were divided into riparian vegetation established along the stream and forest vegetation. Forest vegetation is consisted of secondary forests (seven communities) and plantations (three communities). The urban landscape of Pohang city is dominated by the industrial area. Among them, the steel industry, which occurs large amounts of heat pollution and carbon dioxide, occupies a large proportion. On the other hand, green space is very insufficient in quantity and inferior in quality. This study proposed several restoration plans and further, a green network, which ties the existing green spaces and the green space to be restored as a strategy to improve the environmental quality in this area.

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.75-85
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• 2019

The purpose of this study is to understand the vegetation characteristics of ridges (Gyeongsusan-Seonunsan-Gaeipalsan) in the Seonunsan Provincial Park and to establish reference information for the management of the park in the future. We designated 62 plots with the area of $100m^2$ were installed and analyzed them to investigate the vegetation characteristics. The results of community classification based on TWINSPAN showed seven categories of vegetation communities in the surveyed region: Quercus dentata-Deciduous broad-leaved Community, Quercus variabilis-Pinus thunbergii-Quercus serrata Community, Pinus densiflora Community, Deciduous broad-leaved Community-I, Carpinus tschonoskii-Castanea crenata-Quercus aliena Community, Deciduous broad-leaved Community-II, and Carpinus tschonoskii-Carpinus laxiflora Community. In the vegetation of Seonunsan Provincial Park, coniferous trees such as Pinus thunbergii and Pinus densiflora have been gradually losing their population as part of ecological succession to deciduous broad-leaved trees such as Quercus spp., Carpinus tschonoskii, and Carpinus laxiflora. Moreover, Carpinus turczaninowii, Mallotus japonicus, and others were identified as vegetation reflecting the geographical characteristics of the region neighboring the west coast. The estimated age is 30-60 years, and the oldest tree Pinus densiflora is 63-years old. The index of diversity ($100m^2$) was 0.7942 for Carpinus tschonoskii-Carpinus laxiflora Community, 0.8406 for Carpinus tschonoskii-Castanea crenata-Quercus aliena Community, 0.8543 for Quercus dentata-Deciduous broad-leaved Community, 0.9434 for Quercus variabilis-Pinus thunbergii-Quercus serrata Community, 0.9520 for Deciduous broad-leaved Community-I, 0.9633 for Pinus densiflora Community, and 1.0340 for Deciduous broad-leaved Community-II in the ascending order.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.463-471
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• 2018

Perilla is an oilseed crop cultivated in Korea since ancient times. Due to the high ${\alpha}-linolenic$ acid content in perilla, perilla seed oil can easily become rancid. ${\alpha}-Linolenic$ acid is synthesized by two enzymes, endoplasmic reticulum-localized ${\Delta}15$ desaturase (FAD3) and chloroplast-localized ${\Delta}15$ desaturase (FAD7) in vivo. In order to lower the ${\alpha}-linolenic$ acid content of the seed oil without disturbing plant growth, we tried to suppress the expression of only the FAD3 gene using RNA interference, whilst maintaining the expression of the FAD7 gene. Seventeen transgenic plants with herbicide ($Basta^{TM}$) resistance were obtained by Agrobacterium-mediated transformation using hypocotyls of perilla plants. The transgenic plants were firstly confirmed by treatment with 0.3% (v/v) $Basta^{TM}$ herbicide, and the expression of FAD3 was measured by Northern blot analysis. The ${\alpha}-linolenic$ acid content was 10-20%, 30-40%, and 60% in two, seven, and three of the twelve $T_1$ transgenic perilla plants which had enough seeds to be analyzed for fatty acid composition, respectively. Analysis of the fatty acid composition of $T_2$ progeny seeds from $T_1$ plants with the lowest ${\alpha}-linolenic$ acid content showed that the homozygous lines had 6-10% ${\alpha}-linolenic$ acid content and the heterozygous lines had 20-26% ${\alpha}-linolenic$ acid content. It is expected that the reduction in ${\alpha}-linolenic$ acid content in perilla seed oil will prevent rancidity and can be utilized for the production of high-value functional ingredients such as high ${\gamma}-linolenic$ acid.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.534-539
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• 2018

'Hwawang' is an early maturing and short statured rice cultivar adaptable to the rice-cash crop rotation system that was developed by the rice breeding team of the Department of Southern Crop, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Korea, in 2012. This cultivar was derived from the cross of YR25867 (Hitomebore//YR21247-B-B-B-49-1/Sasanishiki BL4) and YR25866 (Akidagomachi//YR21247-B-B-B-49-1/Sasanishiki BL4) during the 2005/2006 winter season and was fixed as a homozygous line by a doubled haploid breeding system. In the replicated yield trial in 2009, a promising line (YR26253Acp26-1) showed a good phenotype and high yield potential, and so it was selected and designated as 'Milyang256'. The local adaptability test of 'Milyang256' was carried out at three locations from 2010 to 2012. It was named 'Hwawang' and had a high head rice ratio and good eating quality. The culm length of 'Hwawang' averaged 62 cm during the yield trials and was 10 cm shorter than that of 'Keumo'. The number of spikelets per panicle of 'Hwawang' was significantly lower than that of 'Keumo', but the number of tillers per hill was higher. This variety showed resistance to bacterial blight disease but was moderately susceptible to both leaf and neck blast. The milled rice yield of 'Hwawang' was 452 kg/10 a at the late transplanting stage of the local adaptability test. Thus, 'Hwawang' is well adapted to the rice-cash crop rotation system in the southern plain area. (Registration No. 5106)

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.387-395
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• 2018

This study was conducted to identify DNA markers related to resistance to herbicide containing mesotrione in Tongil type rice. Two Tongil type elite lines; Milyang154 and Suweon382, showed resistance to mesotrione, whereas the others were susceptible at 20 days after mesotrione application, and severe growth inhibition was observed in the remaining 13 lines. As a result of analysis of mesotrione resistance using 190 $F_2$ populations derived from a cross of Hanareum2 (susceptible) and Milyang154 (resistant), the mesotrione resistance locus was shown to be a single dominant gene with a 3:1 segregation ratio ($X^2=1.19$, P=0.31). To identify a DNA marker closely linked to the mesotrione resistance gene, bulked segregant analysis (BSA) was adopted. The DNA marker RM3501 was identified on chromosome 2 with a recombinant value of 0.53 to the mesotrione resistance gene. Mst1(t) was located between SSR (simple sequence repeat) markers RM3501 and RM324 with a physical map distance of 10.2 Mb-11.4 Mb on chromosome 2. The band pattern of agarose gel electrophoresis of the SSR marker RM3501 showed the same segregation pattern with respect to mesotrione treatment in 20 Tongil type varieties and a $BC_2F_2$ segregation population derived from a cross between Unkwang (resistant) and Hanareum2 (susceptible). Thus, the RM3501 DNA marker could be used in breeding programs for Marker Assisted Selection in mesotrione resistant rice breeding.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.396-405
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• 2018

The areas of soybean (Glycine max (L.) Merrill) cultivation in Gangwon-do have increased due to the growing demand for well-being foods. The soybean barcode system is a useful tool for cultivar identification and diversity analysis, which could be used in the seed production system for soybean cultivars. We genotyped cultivars using 202 insertion and deletion (InDel) markers specific to dense variation blocks (dVBs), and examined their ability to identify cultivars and analyze diversity by comparison to the database in the soybean barcode system. The genetic homology of "Cheonga," "Gichan," "Daewang," "Haesal," and "Gangil" to the 147 accessions was lower than 81.2%, demonstrating that these barcodes have potentiality in cultivar identification. Diversity analysis of one hundred and fifty-three soybean cultivars revealed four subgroups and one admixture (major allele frequency <0.6). Among the accessions, "Heugcheong," "Hoban," and "Cheonga" were included in subgroup 1 and "Gichan," "Daewang," "Haesal," and "Gangil" in the admixture. The genetic regions of subgroups 3 and 4 in the admixture were reshuffled for early maturity and environmental tolerance, respectively, suggesting that soybean accessions with new dVB types should be developed to improve the value of soybean products to the end user. These results indicated that the two-dimensional barcodes of soybean cultivars enable not only genetic identification, but also management of genetic resources through diversity analysis.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.3
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• pp.225-232
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• 2021

This study sought to investigate the distribution, antimicrobial resistance rate, and bacterial co-infection frequency of non-tuberculous mycobacteria (NTM) in a single center in Incheon, South Korea. A total of 8,258 specimens submitted for tuberculosis (TB)/NTM real-time PCR tests during the years 2015 to 2020 were retrospectively reviewed. In total, 296 specimens (3.6%) were NTM positive, and the positivity increased from 2.5% (30/1,209) in 2015 to 3.8% (66/1,740) in 2020. Of 296 NTM specimens, 54.7% (162/296) were identified as the Mycobacterium avium complex (MAC) followed by the Mycobacterium abscessus complex (MABC) 20.9% (62/296), M. fortuitum 6.4% (19/296) and M. flavescens 3.4% (10/296). Of the NTM-positive specimens, 76.7% (227/296) were tested for drug resistance. The results showed multidrug-resistant NTM in 40.1% (91/227) and extensively drug-resistant NTM in 59.9% (136/227) of these specimens. Of the 145 isolates taken for bacterial culture, bacteria/fungi co-infection with NTM accounted for 43.4% (63/145), in which the most common bacterial species was Klebsiella pneumonia (23.8%, 15/63). This study is the first report on the distribution and antimicrobial resistance of NTM in Incheon. As the proportion of NTM infections increases, active treatment and thorough infection control are required for effective management.